Beacon registration is country specific. When each unit transmits, part of the data is the country it is registered to. If your vessel changes flag state your unit needs to be reprogrammed with the correct protocol.
Bermuda
We have the official form for EPIRB registration in Bermuda.
Canada
Here is the official form for EPIRB registration in Canada.
Cayman Islands
If your vessel is registered in the Cayman Islands you can use a beacon programmed with the US protocol and register it with NOAA. The Cayman Islands Shipping Registry web page covers the procedure.
United Kingdom
Here is the official site for all beacon registration in the UK.
United States
The United States offers an online beacon registration web site for all types of units; EPIRB'S, PLB'S and ELT'S